Python3实现从指定路径查找文件的方法

import os def search_file(file_name, search_path, pathsep = os.pathsep):   for path in search_path.split(pathsep):     candidate = os.path.join(path, file_name)     if os.path.isfile(candidate):       return os.path.abspath(candidate)   return None search_path = 'd://pm//pm' find_file = search_file('babyos.img', search_path) if find_file:   print("File 'babyos.img' found at %s" % find_file) else:   print("File 'babyos.img' not found")